Connector plug



March 2, I943. A. BROWNSTElN 2,312,795 v CONNECTOR PLUG Filed Jan. 5, 1940 12% 22 20 5 W /0 fig l /a.

2, I/ fl INVENTOR I ATTORN EYS atenied 2, 1943 STATES PATENT. OFFI'C fiONNECTOR PLUG Arthur Brownstein, Bridgeport, Conn. Application January 1940, SeriaiNo.- 312,448

3 Claims This invention relates to electrical connector plugs. and more particularly, to connector plugs used with extension cords or conductors for making separable electrical connection to an electrical appliance with a socket in an electrical circuit.

The connector plug of the present invention is preferably formed of some rigid plastic material which can be easily molded, and yet sturdy enough towithstand the usage to whichsuch plugs are put;

The plug body is formed with a pair of spaced blade-receiving slots which extend into the plug from one face thereof and a single cavity opening into the other face of the plug for receiving.

the end 01 a conductor, the cavity communicating with the inner ends of the spaced bladereceiving slots so that the bared end of the conductors may be brought into engagement with the metallic contact blades. The blade-receiving therefore, is to provide a rugged and eflicient electrical connector plug easily molded in one piece, which can be easily assembled without the use of complicated tools.

Other features and advantages will hereinafter appear.

In the accompanying drawing: Figure l is a perspective view of the connector I plug otthe present invention showing the contact blades in assembled position.

Fig. 2 is a sectional viewoi the plug shown in Fig. 1, with the contact prongs removed.

Fig. ,3 is a view taken along line 33 of Fig. 2.

Fig. 4 isa sectional view taken along line 4-4 of Fig. 2.

Fig. 5 is a view similar to Fig. 2, but showingthe contact blades in assembled position and in contact with the bared ends of the wire oi the slots 01' the body are so formed that the blades, when inserted into the same to their proper assembled position, cannot be moved farther into the plug as when the blades are pushed into the receptacle, and, to prevent the blades from being pulled out of the plug body, means are formed on each blade for anchoring the same in the slots against removal."

The blades which are firmly locked in position after they have been properly assembled can be quickly and easily secured in place without the used complicated tools, and in such a manner that they firmly secure the ends of an extension cord or conductor to the plug and at the same time make electrical contact with the bared wires of the cord.

In prior contact plugs, tangs have been utilized to anchor blades in slots in the plug body. However, in these constructions, the tang, which is of resilient material, is forced from its normal position as it passes through the slot and then relies solely upon the resiliency of the tang to snap it into engagement with an abutment.

It is preferred, according to the present invention, however, to provide a tang which does not rely solely upon the resiliency of the prong for moving it into locking engagement with the abutment, but which is positively forced into engagement with the abutment to firmly lock the blade in the slot. While the tang may be resilient and move into cooperative, relation with the abutment when the blade is in place, it is contemplated positively moving it farther intolocking relation.

A further feature of the present invention extension cord.

Fig. 6 is a view taken along line 6-6 of Fig. 5.

Fig. 7 is a perspective view of a contact blade which may be used with the plug shown in the figures just referred to.

Fig. 8 is a view similar to Fig. 7, but showing a diflerent contact blade. I

The connector plug of the present invention includes a body 10 made of rigid plastic material, or any other suitable insulating material,

and preferably is made, as shown, in one piece.

- receiving and supporting a pair of contact blades It is provided with a pair of blade slots II for 12. When the blades I2 are properly assembled in the body,,operative portions thereof project irom a face I3 oi the body while a cable II.

is formed a pair of pockets l8 in which rests the inner ends of the contact blades I! when the same are properly assembled within the plug In assembling the cable and plug, the end of the cable I, with the end or the wires l5 thereof bared, is inserted into the cavity IS. The bared ends of the wires are placed in the blade'slots ll so as to extend thereacross. The-blades are then. inserted into their respective slots until the bared end of the wires are tightly clamped against the end wall of each blade slot. 7

As will be seen from the drawing, the slots II are of a width to receive and hold the blades in position against lateral movement. Each of these slots. is provided with a bowed portion Ila communicating with the slot and into which the end of the wire is positioned when the blades are in place, as will be shown in Fig. 5.

The slots are also provided with a second communicating opening lib, which opens to the inner side of the slot and extends therealong so as to be adjacent the abutment, as shown in Figs. 2 and 5.

With the opening lib so arranged in each slot, the blade having a tang projecting therefrom can be inserted. After the blade is in position in the slot, a bending tool can also be inserted in the opening and along the blade into engagement with the tang, as will be explained.

To anchor the blades in the blade slots'of the plug of the present invention, each blade is provided with a projecting tang I! which is formed by lancing a portion from the blade and then striking down the same so that the tang projects, with slight angularity, from the one at 23 to form a contact blade having two legs of The tang i8 is formed on thisblade, as in the just described blade, by stamp-' equal len th.

ing and bending so that it projects outwardly as shown. Either form of the contact blade may be made from a piece of suitable conducting ma-- terial, such as brass, or may be made from a face of the blade. The blades are inserted into the blade slot so that the tangs l9 project toward each other and pass along the opening lib. The lug i1 is formed at the upper end with a pair of diverging shoulderslll which provide surthe contact blades, the blades are insertedtinto the blade slots and the bared ends of the conductors are tightly clamped against the end wall of the blade slots, and then a suitable tool (not shown) is inserted into the openings ilb andforce is applied to strike down the tangs 19 until thesame pass the shoulders 22 and engage the diverging surfaces of the lug i1.

As was explained above, the angle of the diverging shoulders is such that the tang, when being bent about its base, will be forced into engagement with the surface thereof so as to react thereagainst to press the end of the blade engaging the wire in the slot into better electrical engagement therewith. The tang, in so moving into engagement with the diverging surfaces of the lug ll, will bite into the material of said surfaces which will prevent the tang from being be'nt around and into the passage between the slot II and cavity I. where it might not firmly anchor the blade.

It will be seen that the contact blades will thus be effectively locked in position against longitudinal movement of the blades with respect to the plug. It will, of course, be impossible to move the blades to the rear of the plug as the inner ends of the blades engage the end walls of the blade slots. It will also be impossible to move the contact blades outwardly of the plug body because of the interlocking engagement between the tangs and the diverging surfaces of the lug l1;

When the blades are locked in the slots, good electrical engagement is insured between" wires faces against which the outer end of the tangs body of aluminum and then suitably coated as described in my copending application Serial No. 312,447 filed concurrently herewith.

It will be seen that the connector plug of the present invention may be easily molded from some cheap plastic material and the contact blades may be quickly and easily assembled therewith without the use of complicated tools. Further, the blades, once assembled, are securely locked in their proper position against removal.

Variations and modifications may be made -within the scope of this invention and portions of the improvements may be used without others.

I claim:

1. An electrical connector plug including a single piece body of insulating material, said body comprising a pair of parallel 'siots extending into the same in one direction, a single cavity extending into the body in opposition to said first direction and a pair of passageways diverging from said cavity, each passageway communicating with a slot intermediate the ends thereof, theme wall of each passageway at the entrance thereof into the slot forming an angularly extending shoulderhaving a'flat surface facing the inner end of the slot; at contact blade disposed in each slot; a cord comprising a pair of conductors received within said cavity, the bared end of each conductor extending through a passageway and reversely bent to lie within the inner end of a slot; and rigid tangs lanced from said blades and disposed adjacent the entrance of said passageways into said slots when the blades are positioned in the latter, each tang being adapted to be forcibly bent over about one end into engagement with its adjacent shoulder, the,

angular-1y disposed flat surface intersects the arc through which the end of the tang moves when forcibly bent whereby the end bites therein and locks the blade in the slot and forces the blade inwardly so that the bored end of the conductor is clamped between the end thereof and the inner wall of the slot.

2. An electrical connector plug including a single piece body of insulating material, said body comprising a pair of parallel slots extending into the same in one direction and adapted to receive contact blades; a single cavity extending into the body in opposition'to said first direction and a pair of passageways diverging from said single passageway, each passageway communicating with a blade slot intermediate the ends thereof,

. the one wall of each passageway at the entrance thereof into the slot forming a shoulder angu larly extending relative to said slot and facing the inner end thereof; a contact blade disposed and the contact blades, for, as v in each slot, each contact blade being formed of flat conducting material bent upon itself to form two blades of equal length having the outer ends thereof integrally joined together; a cord comprising a pair of conductors received within said cavity, each conductor of said cord having a bared end thereof extending through a passageway and reversely bend to lie within the inner end of said slot; and means for camming the ends of said blades against the inner walls of said slots, said means comprising portions partially lanced from both legs of each contact blade and forming a tang angularly projecting from one face of the blade to a point adjacent a shoulder, each tang being adapted to be forcibly bent over into engagement with its adjacent shoulder, the angularly disposed surface intersecting the are through which the end of the tang moves and carnming the blades against the inner walls of the slots with the bared end of each conductor tightly clamped between the end of each blade and the inner wall of the slot, the ends of the tangs biting into said shoulder and holding the blade in said position.

3. In an electrical connector plug including a single piece body of insulating material, said body being formed with a pair of parallel slots extending into the slots in one direction, a single cavity extending into the body in opposition to said first direction and a pair of passageways ditang having a flat end face angularly projecting from one face of each blade in the direction of the shoulder, said slots having a communicating opening of less width than the blade and extending there-along to a point adjacent the shoulder and permitting the tang on the blade to pass therealong and a tool to be inserted into said body for forcibly bending each tang .into engagement with a shoulder, the shoulder being so angularly disposed with relation to the slot that the flat end face of the tang, when the latter is bent about its base, engages the flat surface thereof whereby the blade is cammed inwardly and forced into engagement with the bottom of the slot with the bared end of the conductor therebetween, the fiat end face of the tang bitinginto the flat surface of the shoulder and rigidly holding the blade against movement relative to the slot.

ARTHUR BROWNS'I'EIN. 

